Scientists May Have Figured Out Why Dead Brains Don't Always Rot (smithsonianmag.com) 31
fahrbot-bot shares a report from Smithsonian Magazine: The brain is one of the first organs to begin decomposing after death. Yet archaeologists have discovered more than 4,400 preserved human brains around the world, some of which have remained intact for the last 12,000 years. In hundreds of cases, the brain was the only soft tissue left among otherwise skeletal remains. But how and why do brains sometimes persist for millennia while all other types of soft tissue disappear? This preservation paradox has stumped scientists for years. Now, however, a team of researchers say they may have solved the mystery.
If a brain ends up in a wet, oxygen-starved environment, the processes that usually cause decay can have the opposite effect, researchers report in a study published in the August 7 issue of the Journal of Proteome Research. "Under the right conditions, preservation actually arises from decay itself: The same reactions that degrade tissue can also weld the breakdown products together into something far tougher," study co-author Alexandra Seviour, a paleobiologist at the University of Oxford in England, tells Live Science's Victoria Atkinson.
Following experiments on 72 mouse carcasses (described in the article) the scientists think they know why. When oxygen is abundant, it triggers a cascading, chemical chain reaction that causes brain proteins to break down rapidly. This sequence hinges on free radicals, highly reactive, unstable molecules that "steal" electrons from nearby atoms and molecules. The process happens in the brains of living people too, and if left unchecked, can cause health problems. In low-oxygen environments, however, this chemical sequence appears to play out differently. The researchers' analyses hint that free radicals instead react and bond with nearby proteins, making the overall tissue tougher and more resistant to decomposition, Seviour tells Chemical and Engineering News' Anirban Mukhopadhyay. The findings show that "decay is not the opposite of preservation but, under specific chemical constraints, one of its mechanisms," the researchers write in the paper.
If a brain ends up in a wet, oxygen-starved environment, the processes that usually cause decay can have the opposite effect, researchers report in a study published in the August 7 issue of the Journal of Proteome Research. "Under the right conditions, preservation actually arises from decay itself: The same reactions that degrade tissue can also weld the breakdown products together into something far tougher," study co-author Alexandra Seviour, a paleobiologist at the University of Oxford in England, tells Live Science's Victoria Atkinson.
Following experiments on 72 mouse carcasses (described in the article) the scientists think they know why. When oxygen is abundant, it triggers a cascading, chemical chain reaction that causes brain proteins to break down rapidly. This sequence hinges on free radicals, highly reactive, unstable molecules that "steal" electrons from nearby atoms and molecules. The process happens in the brains of living people too, and if left unchecked, can cause health problems. In low-oxygen environments, however, this chemical sequence appears to play out differently. The researchers' analyses hint that free radicals instead react and bond with nearby proteins, making the overall tissue tougher and more resistant to decomposition, Seviour tells Chemical and Engineering News' Anirban Mukhopadhyay. The findings show that "decay is not the opposite of preservation but, under specific chemical constraints, one of its mechanisms," the researchers write in the paper.
Frist Poooooost. (Score:5, Funny)
Re: (Score:3)
Do you want zombies? Because this is how you get zombies.
Way to go science, destroying the world before politicians do.
(/h in case is wasn't blindingly obvious)
Vaccinations. (Score:1)
Vaccinations.
Well not exactly vaccinations. But Humans, especially Americans are bombarded with ever increasing doses of brain rot. First from TV, and now Social Media. By the time some people die their brains have built up a tolerance and are immune to further rot.
Why only brains though? (Score:4, Interesting)
Surely the chemical reactions spoken of would occur in other parts of the body too and stop them breaking down in low O2 enviroments? Is it becaue the brain is sterile compared to the rest of the body so it takes a while for bacteria to get inside and by then it may be too late for them?
Re:Why only brains though? (Score:5, Interesting)
Finally, recalcitrant peptides are depleted in cytoplasmic and mitochondrial domains and strongly enrichedby up to 16-foldin calcium-dependent phospholipid-binding C2 domains. C2 domains mediate Ca2+-regulated binding of proteins to anionic phospholipids on membrane surfaces, (58) and their enrichment indicates that peptide persistence is disproportionately associated with proteins stabilized at membranes, rather than within freely soluble intracellular compartments. Loss of ionic homeostasis and rising intracellular Ca2+ during post-mortem decay (6) would be expected to further promote sustained membrane association of such proteins. Membrane-adjacent microenvironments are structurally constrained, concentrating redox-active substrates and catalysts (such as lipids and metals) while restricting diffusion and oxygen availability relative to the cytosol. In this context, radical oxidation is less likely to proceed via chain propagation, which requires continuous access to molecular oxygen, (59) and more likely to locally terminate via cross-linking. Such cross-linking would be expected to reduce molecular mobility and solubility, sterically hinder enzymatic and hydrolytic attack, and promote the formation of insoluble aggregates resistant to degradation. (60)
A further factor likely reinforcing this taphonomic trajectory is the brain’s unusually large and heterogeneous reservoir of redox-active iron. (61) Nervous tissue contains high iron concentrations relative to most other soft tissues, distributed across multiple pools such as heme proteins, ferritin-bound stores, and iron-rich compartments associated with mitochondria, myelin, and oligodendrocytes. (62) In life, these pools are tightly regulated to support oxidative metabolism while limiting collateral damage. (63) After death, however, progressive membrane failure and loss of regulatory control are expected to alter iron speciation and availability, increasing the likelihood of local metal-catalyzed radical generation. Importantly, such chemistry need not produce uniform oxidative destruction: when redox reactions involving iron occur within membrane-adjacent or diffusion-limited microenvironments, they may favor the formation of short-lived aromatic radicals that terminate by covalent cross-linking rather than by chain-propagating oxidation (Table S22). The enrichment of peroxidaseswhich often involve heme iron or metal cofactors (64)among recalcitrant peptides is compatible with localized, metal-associated redox chemistry, in which iron-containing cofactors may contribute to peroxide-driven radical formation without sustaining chain-propagating oxidation.
The brain is particularly predisposed to follow this trajectory. In life, it is among the most oxidatively stressed organs: it consumes a disproportionate share of oxygen, is rich in redox-active metals, and relies heavily on antioxidant and repair systems to maintain protein integrity. (65) Additionally, the brain combines extreme membrane density, (66) an abundance of structurally stable, long-lived proteins that accumulate heterogeneous oxidative modifications during life, (67) and anatomical sequestration within the cranial vault. Together, these features establish a post-mortem environment characterized by pre-existing chemical and structural heterogeneity, limited molecular mobility, and restricted oxygen exchange: conditions that favor local, diffusion-limited radical reactions and termination by cross-linking rather than runaway, chain-propagating oxidation. Notably, the molecular features that define this post-mortem pathway closely parallel those that stabilize aggregation-prone protein assemblies in neurodegenerative disease: enrichment of -sheet and structurally ordered fragments, (68) redox-active residue modifications, (69) and oxidative cross-links (70) are hallmarks of pathological protein aggregation in vivo. While the biological contexts differ fundamentally, these parallels indicate that common chemical processes govern protein persistence across clinical and geological time scales.
Re:Why only brains though? (Score:4, Informative)
Surely the chemical reactions spoken of would occur in other parts of the body too and stop them breaking down in low O2 enviroments? Is it becaue the brain is sterile compared to the rest of the body so it takes a while for bacteria to get inside and by then it may be too late for them?
This is clearly an intentional design, handed to us by the precursors, the Anunnaki, The Elder Gods and the Flying Spaghetti Monster when they convened to design our living systems. They needed a simple way to preserve the most important part of living entities within the experiment when those living entities proved to be especially useful or resilient, but since they only check on the experiment every twelve thousand years or so, it needed to be a foolproof and easily triggered, not to mention reliable, preservation method. They'll be around to collect the preserved brains of the past cycle any day now, as the experiment is clearly beginning to fall apart on its own and will need guidance to continue. Or it will simply be wiped clean and began again.
RFK Jr (Score:4, Insightful)
We might want to study that guy.
Re: (Score:3)
We might want to study that guy.
Especially as the worm ate part of his brain and then *died*. Sure, "correlation does not imply causation" is usually true, and maybe that was natural causes, but we don't actually know in this case, especially given his preferred diet. (Given the chance, he'd probably eat that worm too.) :-)
Re: (Score:3)
We might want to study that guy.
In a prion isolation facility on the moon.
Brain Rots (Score:1)
Next research question (Score:3)
Why do some alive brains rot?
Re: (Score:2)
Politics. Sadly, there's no cure, save for complete disconnection. Unfortunately that leads to a fork in the road. You become an insufferable, annoying jackass that wants the world to know how great it is to opt out... or you reveal it after the fact when your manifesto is found in the cabin during the manhunt.
So most of us manage our symptoms rather than seek a cure.
Re: (Score:3)
Politics. Sadly, there's no cure, save for complete disconnection. Unfortunately that leads to a fork in the road. You become an insufferable, annoying jackass that wants the world to know how great it is to opt out... or you reveal it after the fact when your manifesto is found in the cabin during the manhunt.
So most of us manage our symptoms rather than seek a cure.
People who truly disconnect don't proclaim it from the rooftops. Performative disconnection is just another segment of political mental illness. "LOOK HOW AWESOME I AM FOR NOT BEING A JOINER!" That's an attempt to connect via performance. The cabin in the woods types that just live and don't bother reconnecting don't really get found out until someone finds the remains, usually years after the fact. We hear about the manifesto types because they're typically just prepping their performative disconnection fo
Re: (Score:3)
There are people who live off-grid or in remote parts of the world, and who run YouTube channels chronicling their adventures. I daresay they still feel "disconnected" and enjoy it, but see no incongruity sharing their situation with others. And they get some income. They're just dealing with the rest of the world on their own terms.
Re: (Score:2)
There are people who live off-grid or in remote parts of the world, and who run YouTube channels chronicling their adventures. I daresay they still feel "disconnected" and enjoy it, but see no incongruity sharing their situation with others. And they get some income. They're just dealing with the rest of the world on their own terms.
I would bet even among those folks there are those just sharing their day with the outside, and those that spend their camera time preaching the gospel of disconnect.
Re: (Score:2)
OTOH, sometimes it's easier to disappear in a city.
But here's the real question (Score:3)
It's cool to know why dead brains don't always rot; but for me the more pressing question is why so many LIVE brains DO rot.
I suspect that being a career politician is a significant risk factor for brain rot among the (perhaps only allegedly) living.
Zombie appropriate chewing gum? (Score:2)
Is this a left or right issue? (Score:1)
What if the right brain does not rot but the left does - does this give you the right to say that you have better brain?
What if the left brain does not but the right does - does this give you the right to say that you left your brain?
Re: (Score:2)
Literal Weekend At Bernie’s situation and the “mainstream media” is utterly silent.
Re: Mitch McConnell (Score:2)
Agreed, I think he's been dead or as close to dead as you can be for a few months now.
Re: (Score:3)
Watch the video of the EMT's loading the ambulance at his home.
If they were any more non-rushed they would have had time for a card game.
If there were even the faintest pulse they would have screamed out of there with sirens blazing.
But TPTB didn't want Massie running in a special election.
Day by day the populous is realizing that "Democracy does not exist".
Re: (Score:2)
One is still collecting a paycheck and the other is not.
Re: (Score:3)
Biden is eligible for a rather generous pension. He served in the Senate from 1973 to 2009, as Vice President for 8 years, and as President for 4 years. So, he's still getting a paycheck. He's just retired and therefore doesn't have to work for it. But he did earn it.
"Why...brains don't always rot" (Score:3)
Sometimes they don't watch TikTok?
Brain Tanning (Score:2)
Merv Griffin (Score:2)
I thought it was because Merv Griffin injected them with window cleaner.